Finally real info. I remember it from when he did it and yes it's an improvement on full fan turbines but still isn't as anywhere near good as a standard 3 blade unit.

2 things stand out he used a windtunnel which is known for giving false readings like this from wall interference preventing the aiir from going around the turbine with so many blades. Yes when he removed blades it went better because they let more air through.

The other is flat blades. Sorry but just not going to cut it aerodynamically.

Some people are easy to fool it seems. Like I say just put physics to work if you want to know what is fact or fiction or in many cases like this, not quite knowing how to do wind tunnel testing. This problem has come up recently in serveral cases. The windtunnel needs to be 4x's the size of the windgen and even then there are effects.

Finally real info. I remember it from when he did it and yes it's an improvement on full fan turbines but still isn't as anywhere near good as a standard 3 blade unit.

2 things stand out he used a windtunnel which is known for giving false readings like this from wall interference preventing the aiir from going around the turbine with so many blades. Yes when he removed blades it went better because they let more air through.

The other is flat blades. Sorry but just not going to cut it aerodynamically.

Some people are easy to fool it seems. Like I say just put physics to work if you want to know what is fact or fiction or in many cases like this, not quite knowing how to do wind tunnel testing. This problem has come up recently in serveral cases. The windtunnel needs to be 4x's the size of the windgen and even then there are effects.

Architect, Just because one is good in one area doesn't mean they are good in others.

Yes I know exactly the difference between a spinnaker and a mainsail. One is eff and the other isn't. Guess which one isn't? PS I design, build 25knot cruising sailboats, live on, race and cruise them. And on them a classic spinnaker isn't useful because they go faster downwind by tacking from one broad reach to the others allowing a high apparent wind going so much faster even with the extra distance.

The only reason a spinnaker works on a monhull well is it's so slow. My Cats, Tri's are 4x's as fast so only special lift, not drag spinnakers are used.

As an illistration I once sailed a Mega 30 monhull but fast though a racing fleet like I had my own private wind. How is the wind was about .5mph out of the aft quater/broad reach. I caught it, not easy and slowly pulled in the sails tighter which increased over the deck windspeed/apparent wind. As the boat went faster, about 1mph added to the wind speed made it go faster. I got it going about 2mph that way while all the other boats sails just flopped around from the waves. Guess which ones had spinnakers up?

Fact is drag is just that. At low blade speed of a drag based fan just can't extract much power because it resists!!! Because of this resistance you are so proud of the wind mostly just goes around the rotor.

Vs a low blade/area ratio/2-5blades, allows the wind to go through easily, more of it and faster. Without all the air friction and blade interference drag of a many bladed rotor the blade can go many x's the windspeed at the outside end allowing it to work in 100=300mph winds to extract power. Vs just the windspeed for the drag style.

Please put up the specs, more info but basic physics, what I use to judge everything, it doesn't look good for Bill.

For referece eff for 2 blades about 48%, 3blades, 56%, 4 blades 42%, 5 blades 38% IIRC and eff drops off from there. The Fan type used for pumping water is less than 10% eff. They do it on purpose so it survives high winds better and just need torque to pump a little water so eff doesn't matter much as ruggedness.

If it's so good why don't you build it and make a fortune? Put your money up like I'm doing.

I bummed because I can see about 40 of these windmills on the horizon and just the other morning when it was very windy they were all sitting there not spinning. The fact is there was plenty of energy there. But the inferstructure to be able to store and use this energy is just not in place.

I can't wait until engineers are able to find the way to store and continue to make this technology more efficient and more profitable. I know it will be a while before engineers are able to conquer some of the larger problems with the system. But I can't wait.

I agree that some of the aerodynamics improvements have made racing less exciting. However, I think technology has also made racing more exciting. I disagree a little bit with this article because it focuses so much on aerodynamics. There is so much more to racing. I am in awe that taking 1/2 pound of air out of the left front tire can really make that much of a difference in how the car drives. But it does. Absolutely awesome.

I agree. Going away from the human element would decrease crowd size as well as make things too automated. Part of the fun of racing is watching someone take a risk that a computer wouldn't take and succeed causing them to win the race.

In quite a few races the difference between winning and losing is knowing how much gas is left in the tank and often that is a little bit more than an educated guess. But not much more.

Steamlining, or reducing the airflow drag, is certainly the best way to get "free horsepower" for racecars. IT^ does get complex when there are multiple cars close together, though. Drafting is a bit different, it works for most cars on the road. We proved that back in 1967, using vacuum gauges to measure "effective engine load", which was a lot cheaper than an air tunnel or dynamometer. The problem with doing experiments on the local interstate is the way other folks get so upset at seeing two cars six inches apart. But it is safer than you might think, because if the front car slows quickly the second car catches up quickly and so the impact is quite small.

The number of blades on the big wind turbines is the result of a compromise that includes cost and weight, rather than being based just on maximum energy recovery. Otherwise they would have more blades.

Reducing the drag on "big trucks" is a very valuable effort because of the large number of them around. I am waiting for somebody to try air dams on the trailers and some sort of means to avoid the high-vacuum turbulence that I see behind the trailers. I have thought for some time that lowering the box three feet could do a lot to reduce the drag, but there are a lot of other considerations, it turns out. BUt I have seen a lowered tanker truck and it did look a lot more stable than the standard ones. IT would be very educational to hear what the research folks have come up with relative to steamlining trucks. After all, even a 1% reduction in fuel consumption would save a whole lot of money.

Yes Bil was either lying or just plain wrong. I design, build windgenerators among other things, presently doing 2 2kw designs for production.

And mine will hit 35-40% eff, not 20%

Facts are the best wind power collectors are 3 blade rotors like you see on most all cost effective WG's. As more blades are added they just interfer with the ones before it and add drag, lower tip speed needed to make real power. Basic physics, deal with it and stop making ill informed statement.

Do you know why there is a Belt's limit? Air flowing to a WG if too much energy is taken, the wind slows down in front of the WG rotor and goes around it instead.

I've done every type of WG including fast 20-30mph sailboats and physics holds well on all of them. Sadly means any WG with more than 5 blades just isn't going to be eff, cost effective.

If you think Bill's WG is so good build them and make a fortune. Until you build and prove your points it's just misinformed vaporware or just a plain scam.

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